Seed treatment apparatus

ABSTRACT

A seed treatment apparatus provides for minimal waste of products for treating seeds, in that it is precisely controllable and automatically adjustable. A volume of seeds to be treated and a flow rate of treatment product for treating the seeds can both be sensed. At least one of the flow rate of the treatment product and the volume of seeds can automatically be adjusted if it is determined that a ratio of the flow rate of treatment product to the volume of seeds is not the same as a predetermined flow rate to volume ratio.

RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.14/309,563, filed Jun. 19, 2014, which is a continuation of U.S. patentapplication Ser. No. 12/848,412, filed Aug. 2, 2010, which claims thebenefit of U.S. Provisional Application No. 61/273,325, filed Aug. 3,2009, the disclosures of which are hereby fully incorporated byreference in their entirety.

FIELD OF THE INVENTION

The present invention relates to an apparatus for surface treatment ofseeds and more particularly to a seed treatment apparatus that minimizeswaste of treatment products.

BACKGROUND OF THE INVENTION

Seeds that are planted for agricultural and other purposes are oftentreated prior to planting. The treatments may accomplish variouspurposes including attacking target bacteria, molds and fungus that cancontaminate seeds or that may be present in the soil. Also seedtreatment can include insecticides, pesticides and provide deterrence orprevention of insect and other animal pests that would target seeds.Treatments may also provide fertilizer. Direct application of seedtreatment allows for a reduction in the amount of treatment compositionthat would be required by application to soil after planting for many ofthe beneficial effects. Post-planting application may not penetrate thesoil to a level or location where it would be effective, is weatherdependent, and may not be as economical as direct seed application.

Preplanting treatment of seeds, however, involves applications ofchemicals and other agents that are expensive and may even be toxic tothe environment and workers. Various devices for treatment of seeds inbatch or continuous treatment mode are known. U.S. Pat. No. 5,891,246 toLund, the disclosure of which is hereby incorporated by reference,describes a seed coating apparatus for applying a coating fluid wherebyseeds are dispersed with a seed dispersing member. U.S. Pat. No.4,657,773 to Mueller, the disclosure of which is hereby incorporated byreference, describes a process and apparatus for dressing seed in whichseed is guided over a dispensing cone through a jet of dressing and ontoa rotary table. German patent No. DE 4411058 to Niklas, the disclosureof which is hereby incorporated by reference, describes a device with amixing bowl connected to a high speed, multi-turn actuator and amechanism to feed seed into the mixing bowl. The bowl rotates to rotateseed being treated therein. The seed treating formulation is sprayed inthe bowl while the seed is being rotated to uniformly coat the seed withthe formulation.

Such treatment apparatuses typically apply treatment products to theseeds at a uniform rate to each batch of seeds and cannot adjustapplication rate as circumstances dictate, such as, for example, upon aslowing of the feed rate to the seed treating equipment. A significantamount of chemical waste can be generated by applying excess treatmentproducts to batches of seeds without precise controls. Because treatmentproducts can be very expensive, e.g., hundreds of dollars per gallon,this can result in a large economic loss. Such chemical waste can alsoresult in an environmental hazard. Accordingly, there is a need for animproved way to control the amount of treatment products applied to theseeds to minimize waste, particularly at the retail seed level.

Certain computerized large scale seed treaters can adjust applicationrate based on the weight of “flow” of seeds being processed. That is theseed being conveyed to the treatment applicator is weighed and theapplication rate may be varied based on the flow rate as measured byweight. There is room for improvement of this methodology as such flowweight measurement is taken over a length of the seed flow and thusrequires averaging and cannot readily accommodate dramatic seed flowinterruptions or variance. Moreover such equipment is expensive and notgenerally suitable for use at the retail level. Moreover, the weight ofthe seed can vary with humidity and then more or less than the optimalamount of treatment fluid may be applied to the seed.

The amount of seed treatment provided to seeds is conventionallydetermined by the weight of seeds, for example, x volume of treatmentfluid for y weight of seeds. A useful measurement to determine theamount of treatment products needed, as well as controlling the rate ofcoating, is the total surface area of the seeds. The weight of seeds canvary with humidity and other factors whereas the volume of seedcorrelates more directly with the surface area of the seed.

For certain treatments, including formulations several of treatmentsapplied simultaneously to the seeds, the seeds need to be planted verysoon, within hours after application, for optimal effectiveness. Suchseed treatment needs to be done at a local level by the seed retailer.This is problematic with existing seed treaters with automaticallyadjusted treating controls as such are expensive and typically are noteasily used for repeated and rapid processing small batches forindividual users.

SUMMARY OF THE INVENTION

The apparatus of the invention is directed towards and resolves theissues described above. The seed treatment apparatus provides forminimal waste of products for treating the seeds, in that it isprecisely controllable and automatically adjusts one of a treatmentproduct flow rate and a volumetric feed rate of the seed to the atomizerin response to a change in the other. Moreover, the device iscontrollable for end of batches to eliminate treatment dispensing afterthe seed flow has ceased. The device is economical and can be readilyutilized by the seed retailer for small batches and the set-up time andeffort for a new batch is minimal.

The device, in a preferred embodiment, generally comprises a seed inlet,a seed metering portion, a treatment application portion, a treated seeddischarge, and a plurality of treatment tank units, and a controlprocessor. The device may have a tumbler drum intermediate the treatmentapplication portion and the seed discharge. Each treatment tank unitincludes controllable metering pumps controlled by the control processorand in flow communication with the treatment applicator portion. Theprocess controller has a user input, and is connected to the pluralityof treatment tank units, the seed metering portion, and the treatmentapplicator portion. The process controller receives batch data from theuser/operator, including treatment composition, treatment applicationrate, and seed treatment rate. The treatment composition is theformulation of the treatment fluid to be applied in precise proportionsas selected from the plurality of treatment tank units. The treatmentapplication rate is the amount of treatment fluid to volumetric measure(or weight in some embodiments) of seed. The seed treatment rate is rateof processing the seed through the device. The level sensor is connectedto the process controller.

Seeds are deposited through the seed inlet, such as a hopper, into themetering portion which is configured as a seed wheel. The seed wheel hasprecise volumetric metering compartments circumferentially spaced aroundthe wheel. As the wheel is rotated the compartment under the inlet fillsand is rotated with excess volume in the compartment retained in theinlet. Opposite the inlet, the volumetric metering compartmentsdischarge their contents into the treatment applicator portion,preferably an atomizer configured as an apertured rotating plate. Asensor in the inlet suitably positioned provides a signal indicating thelevel of the seed in the inlet. The sensor is connected to the controlprocessor and allows control of the rotation of the seed wheel such thatthe wheel does not commence rotation and the flow of seed until thecompartments are readily fillable at the seed inlet with seed. Moreoverthe application portion does not activate to dispense treatment fluiduntil seed dispensed by the seed wheel enters into the applicationportion. The seeds are metered volumetrically into the applicationportion by the seed wheel rotation speed. This is typically entered bythe user into the control processor at the commencement of a new batchor may be saved within the control processor and automatically selected.As the seeds are discharged from the seed wheel, the seeds fall and aredistributed over a dispersion cone and into a spray curtain of treatmentfluid provided by an atomizer wheel. At the atomizer wheel, the seedsare coated with treatment products and then are gravimetricallydispensed into a tumbler drum where they are rotated to provide forfurther uniform coating. The seed is dispensed from the tumbler forpackaging or transport to the planting location. Treatment products arepumped from one or more tanks into the atomizer wheel for application toseeds. Pumps are controlled to precisely regulate the flow of treatmentproducts through pumps at a desired rate that is tied to the seed feedrate. The computerized process controller can automatically adjust atleast one of the volumetric flow rates of the treatment products or thevolume rate of flow of seeds entering the atomizer at any given time ascontrolled by the seed wheel to optimize the amount of treatmentproducts provided and to minimize waste. If the user decides to slow theseed processing rate by manually reducing the rate at the user input ofthe control processor, the control processor automatically reduces therate of treatment fluid pumped into the applicator portion, theatomizer.

A feature and advantage of the present invention is reduction of wasteof treatment products in treating seeds. Seeds are metered by volumebecause volume has a direct correlation to surface area, unlike weightor number of seeds, which determines the amount of treatment productsnecessary to coat the seeds. By adjusting the amount of treatmentproducts pumped from the tanks as a function of the volume of seedsbeing treated, waste of excess treatment products can be minimized.

Another feature and advantage of the present invention is that the rateof flow of seeds through the system can be adjusted without compromisingthe quality of seed treatment. The seed flow rate can be manuallyadjusted using the system's control panel. When the seed flow rate isadjusted, the system automatically increases or decreases the fluidapplication rate from the pumps to accommodate the correspondingincrease or decrease in seeds that are being treated. This preventseither under treating seeds or producing waste from applying excessivetreatment products.

Another feature and advantage of the present invention is that existingseed treatment apparatuses can be retrofit with one or more elements ofthe disclosed invention to allow them to adjust the fluid applicationrate based on the volume of seeds to be treated.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of a portion of a seed treatment apparatusaccording to an embodiment of the present invention.

FIG. 1A is a cross-sectional view of the portion of a seed treatmentapparatus of FIG. 1 taken along the line 1A-1A.

FIG. 1B is a cross-sectional view of the portion of a seed treatmentapparatus of FIG. 1 taken along the line 1B-1B.

FIG. 2 is a perspective view of a seed treatment apparatus according toan embodiment of the present invention.

FIG. 3 is a flowchart of process steps taken to coat seeds withtreatment products according to an embodiment of the present invention.

FIG. 4 is a partial view of a seed treatment apparatus according to anembodiment of the present invention.

FIG. 5 is a flowchart of process steps taken to operate a seed treatmentapparatus according to an embodiment of the present invention.

FIG. 6 is a flowchart of a process for retrofitting a seed treatmentsystem according to an embodiment of the present invention.

DETAILED DESCRIPTION

Referring to FIGS. 1, 1A, 1B and 2, there can be seen elements of a seedtreatment apparatus 100 according to an embodiment of the presentinvention. Seed treatment apparatus 100 can include a housing 102including an inlet 104, a seed wheel 106, a dispersion cone 108, anatomizer wheel 110, and an outlet 112. Housing outlet 112 can connect toa polishing drum 114 or mixing chamber. The atomizer wheel 110 can befluidly connected to one or more 15 treatment tanks 116 containingproducts for treating the seeds via an inlet tube 118. The system can beconnected to a computer system with a processor having a control panel120 for monitoring and/or adjusting the system.

FIG. 3 depicts a flowchart showing a process 200 by which seeds can betreated according to an embodiment of the present invention. Seed canfirst be fed into the apparatus at the housing inlet at step 202 suchthat it travels through the apparatus under the influence of gravity. Ina preferred configuration, the apparatus is therefore verticallyarranged. After entering the housing, the seed travels into and fillsmetering compartments, such as slots, in the seed wheel at step 204. Theseed wheel is configured to collect a predetermined quantity of seed asit rotates to ultimately dispense the seed. In one embodiment, the seedwheel meters the seed based on a volume of the seed. This isadvantageous because the amount of seed treatment needed is mayadvantageously be based on surface area, which correlates moreaccurately to volume than to other metering measures, such as weight andnumber of seeds. Seed wheel can be rotated by a motor, such as, forexample, a ⅓ horsepower variable speed motor, to dispense the seed onceit has been metered and to rotatably fill each adjacent slot in thewheel. After being dispensed from the seed wheel, seed falls onto thedispersion cone at step 206. The dispersion cone dispenses the seedsgenerally uniformly into the spinning atomizer wheel at step 208 into acurtain of treatment fluid provided by the atomizer to coat the seeds atstep 210. Seeds are then ejected out of the housing outlet at step 212and can then be further processed or packaged at step 214.

Referring to FIG. 4, there can be seen a portion of a seed treatmentapparatus 100 incorporating a seed wheel 106 according to an embodimentof the present invention. Seed wheel 106 can include a plurality ofradially inwardly extending slots 122 for containing seed positionedthere around. A grader 124 can be positioned at a top portion of seedwheel 106 and connected to housing 102 such that it remains stationaryas housing 102 rotates. Grader 124 can be positioned forward of inlet104 relative to the direction of rotation of seed wheel 106 so that asseed is input through inlet 104 and into seed wheel 106 as it is rotatedby motor 126, the grader 124 levels the seed to ensure a uniform volumeof seed in each slot 122. One or more sensors (not pictured) can bepositioned above the seed wheel 106 to provide the control processordata on the amount of seed in the inlet 104 which correlates to when theseed wheel slots 122 will stop being filled with seed and alsocorrelates with when the seed will stop being deposited on the cone 108and passing into the seed treatment region. Importantly, the controlprocessor can then shut down the treatment fluid flow when the seed willstop passing through the seed treatment region. In one embodiment, theseed level sensor is a capacitive sensor such as those available fromTurck, Inc.

The treatment portion can have an atomizer wheel 110 that receivestreatment fluid from the treatment tank units 116 through an inlet tube118 and disperses the fluid onto seeds. Atomizer wheel 110 is designedto apply treatment products at a constant rate to evenly coat each seed.In one embodiment, it can apply treatment products by atomizing themonto a falling curtain of seed before the seeds are discharged. Afterseeds are treated at the atomizer wheel 110, they can be discharged outof the housing 102 into a tumbling drum 114 for additional coating ofthe seeds by seed to seed contact. The drum then may discharge the seedfor packaging or transport to the planting location. In anotherembodiment, seeds can be discharged from housing for packaging andtransport without further processing in drum 114.

Operation of atomizer wheel 110 can be tied to seed wheel 106 such thatwhen seed wheel 106 stops rotating (because of a pause in operation orbecause there is no more seed left to treat), atomizer wheel 110 canstop operating either at the same time or at a predetermined timeshortly afterwards.

Treatment products are received into the atomizer wheel 110 through aninlet tube 118 that is fluidly connected to one or more treatment tankunits 116. Tank units can include premix tanks designed to mix liquidtreatment products requiring dilution or agitation. Premix tanks caninclude motorized rotating paddles and internal baffles for mixing thetreatment products and providing suspension of the liquid with minimalfoam. Non-mixing tanks can also be connected to atomizer wheel, such as,for example, water tanks, bulk tanks and dye tanks.

Pumping systems 128, such as peristaltic pumps, draw treatment productsfrom tanks and dispense them to the atomizer wheel through fluid lines.Pumping system can include flow meters for measuring and/or regulatingthe amount of product being dispensed. Fluid lines can enter a staticmixer to mix treatment products from various tanks before entering inlettube.

Seed treatment apparatus 100 can include a computerized treatment systemthat proportions amounts of seed and treatment products to provide forminimal treatment product waste. Computerized treatment system caninclude sensors, flow meters, and/or controls to monitor/control boththe flow rates of the treatment products coming out of the pumps and themetered volume of seeds released from the seed wheel. Based upon apre-programmed algorithm, the system can automatically adjust the flowrates of the treatment products based on the volume of seeds to betreated at a given time to control the amount of treatment productapplied to the seeds. Thus, if a flow sensor sensing the flow rate ofthe treatment products and a seed sensor sensing the volume of seedsindicate that the ratio of flow rate to volume is not within a desiredamount of a predetermined optimal ratio or a range of ratios, the systemcan automatically adjust the flow rate and/or the volume. This providesa more accurate distribution of treatment product because thecorrelation of volume of seeds to amount of treatment product needed ismore accurate than a correlation to number of seeds or weight of seeds.

The system can also include a display providing the information to auser and allowing the user to make manual adjustments to the parameters.Display can allow a user to calibrate flow rates for treatment productsand seed and to set other parameters, such as the amount of time thepumps should run and the specific chemical recipe of the treatmentproducts that is to be applied. A user can also enter a desired ratiobetween flow rate of treatment products and volume of seed for thecomputer system to follow in automatically adjusting the flow rate asthe volume of seed varies. Alternatively, this ratio can bepreprogrammed in the system for the specific type of seed and treatmentcomposition.

FIG. 5 depicts a flowchart depicting one example of user operation 300of an embodiment of seed treatment apparatus according to the presentinvention. Initially, the system must be powered on at step 302. Theuser can then enter the desired fluid application rate that dictates theoperation of the pumps at step 304 and the seed feed rate than iscontrolled by the speed at which the seed wheel rotates at step 306. Theuser can then deposit seed in the seed inlet and activate the coatingprocess for treating the seeds at step 308. The treating process willcontinue automatically as described above until all of the seed iscoated. As the treating process takes place, the user can optionallyadjust the seed feed rate at step 310. If the seed feed rate isadjusted, the fluid application rate will automatically be adjustedproportionally. Once all of the seed has been treated, at step 312 thesystem can be shut off.

Adjustment of application of treatment products relative to volume ofseeds can be especially useful at the end of a series of seed batches.For example, a mass of seeds may be deposited into the inlet. The seedwheel then rotates at a predetermined rate, filling each slot with themetered volume of seeds. However, at the end of the mass of seeds, ifmore seeds are not deposited directly on top of the previous seeds, thelast slot on the seed wheel to be filled may not be filled to the presetmetered volume. In this situation, the amount of treatment productpumped into the atomizer for this final batch of seeds would be reducedproportionally based on the volume of seeds as measured by the seedlevel sensor. This can prevent a large amount of treatment product wastefrom this final batch. In addition, during operation there may be timeswhen it is desirable to either increase or decrease the rate at whichseed is fed into the seed wheel. When the seed rate is manuallyadjusted, the system can automatically adjust the pump output to matchthe increase or decrease in seed volume in each batch of seeds so thatthere is not either too much or too little treatment product applied.

In a further embodiment, an existing system utilizing pumps for applyingtreatment products to seeds can be retrofit with the above describedsensors, flow meters, controls, etc. to convert the system into one thatmodifies pump volume based on seed flow. Retrofitting an existing systemcan include some or all of the steps 400 depicted in FIG. 6 in anyorder. The existing system may already include a seed inlet, a means fordispensing seeds, a means for coating seeds and a pump system forsupplying treatment products to seeds. Steps that could be takeninclude, for example, replacing the means for dispensing seeds with thevolumetrically-based seed wheel described above or installing a seedlevel sensor in the means for dispensing seeds for measuring the volume(or weight) of seeds being dispensed at step 402, installing one or moreflow meters for measuring the speed and/or volume of treatment productsbeing pumped to the means for coating seeds at step 404 and installing acomputer system, display, and/or software to allow the fluid applicationrate and seed flow rate to be modified and to automatically adjust theoutput of treatment products from the pumps based on the volume of seedsto be treated at step 406.

What is claimed is:
 1. A seed treatment apparatus, comprising: a housinghaving a seed inlet for receiving seeds and a seed outlet for dispensingthe seeds; a control processor; a seed meter disposed within the housingfor volumetrically measuring and dispensing the seeds thereby providinga controlled volumetric flow of seeds, the seed meter controlled by thecontrol processor, wherein the seed meter comprises a rotatable seedwheel having an outer surface and a plurality of slots for containing ametered volume of seeds; a seed treatment applicator for receiving seedsfrom the seed meter and treating the seeds; a plurality of treatmenttank units each with a treatment fluid, each treatment tank unit with apump controlled by the control processor, each treatment tank unit beingin fluid communication with the seed treatment applicator, whereby thevolumetric flow of the treatment fluid is controlled by the controlprocessor; the process controller communicatively coupled with the seedmeter and the treatment tank pumps, wherein the process controllerautomatically adjusts at least one of the volumetric flow of treatmentfluid and the volumetric flow of seeds in response to a change in theother thereby maintaining a predetermined ratio of the flow rate oftreatment fluid to the volumetric flow of seeds; and a seed sensordisposed adjacent the seed meter for sensing a volume of seeds to bedispensed from the seed meter to the seed treatment applicator, the seedsensor connected to the control processor; wherein each one of theplurality of slots extends across the length of the rotatable seed wheeland is parallel to an axis of rotation of the rotatable seed wheel, andwherein the apparatus further comprises a tumbling drum for additionalcoating of the seeds by seed to seed contact, wherein the tumbling drumis positioned between the seed treatment applicator and a seed dischargeportion.
 2. The apparatus of claim 1 wherein each treatment tank unithas a flow sensor disposed adjacent each respective treatment tank forsensing a flow rate of respective treatment fluid being dispensed to theseed treatment applicator.
 3. The apparatus of claim 1, wherein the seedtreatment applicator comprises an atomizer configured as a rotatingplate for applying the treatment fluid to seeds and a dispersion conethat generally uniformly disperses the seeds around the atomizer.
 4. Theapparatus of claim 1, further comprising a control panel connected tothe control processor whereby a user monitors and controls the flow oftreatment fluid and the volumetric flow of seeds and adjusts one of theflow of treatment fluid and the volumetric flow of seeds whereby thecontrol processor automatically adjusts the other of the flow oftreatment fluid and the volumetric flow of seeds.
 5. The apparatusaccording to claim 1, wherein the apparatus further comprises a motorconfigured to dispense a seed after the seed has been metered and torotatably fill an adjacent slot in the seed wheel.
 6. The apparatusaccording to claim 1, where one or more of the plurality of treatmenttank units comprises a premix tank.
 7. The apparatus according to claim1, further comprising a grader positioned at a top portion of therotatable seed wheel.
 8. The apparatus according to claim 1, wherein thecontrol processor is configured to receive batch data from an operator.9. The apparatus according to claim 8, wherein said batch data areselected from the group consisting of treatment composition, treatmentapplication rate, seed treatment rate, or any combination thereof.
 10. Amethod of treating seeds with the seed treatment apparatus according toclaim 1, the method comprising: depositing a plurality of seeds throughthe seed inlet in the seed treatment apparatus into the seed meter;controlling the seed meter by the control processor to provide avolumetric flow rate of seeds passing therethrough; sensing the seed inthe inlet above the seed meter and sending data to the control processorfor determining when the seed meter will run out of seed for metering;discharging the seeds from the seed meter at the volumetric flow ratethrough a seed treatment region of the seed treatment applicator;individually pumping from each of the plurality of treatment tank unitstreatment fluid into the seed treatment applicator and controlling eachpump by the control processor thereby regulating a volumetric flow rateand thereby coating the seeds passing through the seed treatment regionat a predetermined ratio, with the treatment fluid from the plurality oftreatment tank units; discharging the treated seeds from the seedtreatment applicator; wherein when one of the flow rate of the treatmentfluid pumped to the seed treatment applicator and the volumetric flowrate of seeds changes during the seed treatment, the other isautomatically changed by the control processor thereby maintaining apredetermined ratio of the volumetric flow rate of treatment fluid tothe seed volumetric flow rate.
 11. A method of adjusting the applicationof a treatment-fluid to a plurality of seeds in the seed treatmentapparatus according to claim 1, the method comprising: depositing seedinto the seed inlet to be fed into the rotatable seed wheel andcontrolling by the rotation of the rotatable seed wheel a volumetricfeed rate of seeds to be treated in the seed treatment apparatus with acontrol processor; dropping the seeds from the seed wheel into a seedtreatment region of the seed treatment applicator, controlling thevolumetric flow rate of the treatment fluid for coating the seeds by thecontrol processor in a predetermined ratio of volume of treatment fluidto seed volume; monitoring the volumetric flow rate of the treatmentfluid and the volumetric feed rate of the seeds by the controlprocessor; and automatically adjusting by the control processor thevolumetric flow rate of the treatment fluid when the volumetric feedrate of seeds changes, and automatically adjusting by the controlprocessor, the volumetric feed rate of seeds when the volumetric flowrate of the treatment fluid changes, thereby maintaining thepredetermined ratio of volume of treatment fluid to seed volume.
 12. Amethod of treating seeds with the seed treatment apparatus according toclaim 1, the method comprising: depositing a plurality of seeds throughthe seed inlet in the seed treatment apparatus into the seed meter;controlling with the seed meter a volumetric flow rate of seeds passingtherethrough; sensing the seed in the inlet above the seed meter andsending data to the control processor for determining when the seedmeter will run out of seed for metering; discharging the seeds from theseed meter at the volumetric flow rate through a seed treatment regionof the seed treatment applicator; pumping a treatment fluid into theseed treatment applicator at a volumetric flow rate thereby coating theseeds passing through the seed treatment region at a predeterminedratio, with treatment fluid; discharging the treated seeds from the seedtreatment applicator; determining with the control processor when theseed meter will run out of seed based on sensing the seed in the seedinlet and stopping the pumping of the treatment fluid when the seed willstop passing through the seed treatment region; wherein when one of theflow rate of the treatment fluid pumped to the seed treatment applicatorand the volumetric flow rate of seeds controlled by the seed meter isautomatically adjusted during the seed treatment when the other ischanged thereby maintaining a predetermined ratio of the volumetric flowrate of treatment fluid to the seed volumetric flow rate.